01The verdict: is South Coffeyville water safe?
South Coffeyville's tap water meets most EPA standards but has areas that warrant attention. With a grade of A- (86/100), some contaminant levels or compliance issues suggest that residents may benefit from additional filtration. The city's 1 water system serves approximately 790 residents using surface water (rivers, lakes, or reservoirs).
2 unresolved violations on record
EPA records show open compliance items for this system. Most are administrative, but unresolved items are worth watching.
See what was cited ↓Lead is well under the limit
90th-percentile lead is 2.7 ppb — beneath the 15 ppb federal action level and under the 5 ppb watch threshold.
See the trend ↓7 violations in the last five years
Recent compliance history is the best predictor of future problems — the year-by-year record is below.
See the record ↓South Coffeyville's drinking water received a grade of A- (86 out of 100), indicating good water quality. The city's 1 water system serves approximately 790 residents using purchased surface water.
Lead levels were measured at 2.7 ppb (90th percentile), well within EPA limits. This system has not yet been tested for PFAS under the EPA UCMR 5 program. The system has 18 violations on record, including 3 health-based violations. 2 remain unresolved.
South Coffeyville ranks #40 out of 357 cities in Oklahoma for water quality, placing it above average in the state. The city draws from surface water sources, which are more susceptible to seasonal runoff and agricultural contamination, requiring extensive multi-barrier treatment including coagulation, filtration, and disinfection. As a small community water system, South Coffeyville may have fewer resources for advanced treatment technologies and infrastructure upgrades compared to larger utilities. The system has seen 7 violations in the past five years, suggesting a pattern of compliance challenges that residents should monitor closely.
02What's in South Coffeyville's water
Every contaminant flagged in South Coffeyville, on one shared scale: distance to its own legal limit. The red line is the limit — anything past it is out of compliance, and the closer a bar gets, the less headroom the system has.
Full contaminants report
| Contaminant | Detected Level | EPA Limit | Unit | Category | Status |
|---|---|---|---|---|---|
| Lead (90th percentile) LeadHeavy Metal A toxic heavy metal that can leach into drinking water from older pipes, solder, and fixtures. No amount of lead in water is considered safe. Health EffectsBrain and nervous system damage in children, kidney damage, high blood pressure, and reproductive problems in adults. EPA Limit15 ppb action level Common SourcesCorrosion of lead pipes, lead solder, brass faucets, and household plumbing. | 2.7 | 15 | ppb | Inorganic | Safe |
Cities ranked by 90th-percentile lead PF PFAS in Oklahoma
Cities ranked by compounds detected Cu Copper in Oklahoma
Cities ranked by 90th-percentile copper
03South Coffeyville's ten-year track record
Each box is one year. A green check means no EPA violations; a numbered badge counts that year's violations — red if any were health-based, amber if they were monitoring or paperwork issues. The system has 18 violations on record, including 3 health-based violations. 2 remain unresolved.
6 of the last ten years were clean. The numbered years had EPA violations — red when any were health-based, amber when they were paperwork or missed-testing issues.
▲ Up 2.7 ppb since 1995. Latest reading: 2.7 ppb (2023) — 18% of the action level. Sampled at higher-risk homes (90th percentile).
04Where South Coffeyville's water comes from
South Coffeyville's drinking water comes primarily from surface water sources such as rivers, lakes, or reservoirs.
Purchased Surface Water
Rivers, lakes, or reservoirs — more exposed to runoff, agriculture, and seasonal swings than groundwater.
Wholesale supplier
Multi-barrier treatment: coagulation, sedimentation, filtration, and disinfection to meet EPA standards.
1 system
1 water system, operated under local government ownership.
790 people
Residents served across South Coffeyville's service area.
Surface water systems require multi-stage treatment including coagulation, sedimentation, filtration, and disinfection to meet EPA Safe Drinking Water Act standards. These sources can be impacted by seasonal changes, stormwater runoff, upstream agriculture, and industrial discharge. The system is operated by local government ownership and serves approximately 790 people through 1 water system.
| System name | PWSID | Population | Source |
|---|---|---|---|
| SOUTH COFFEYVILLE | OK3005305 | 790 | Purchased Surface Water |
Water bodies near South Coffeyville
As a surface-water system, these water bodies may directly influence South Coffeyville's drinking water supply.
05Pressure on South Coffeyville's watershed
Outside forces that shape what reaches the treatment plant. None of these is a verdict on the tap by itself — but each adds pressure worth knowing about.
Industrial discharge
5 facilities within 10 miles reported 58k lb released to surface water in the latest EPA Toxics Release Inventory. Proximity doesn't equal tap contamination — treatment and hydrology decide — but it's pressure on the watershed.
Flood & storm history
2 federal disaster declarations on record for Nowata County. Flooding and severe storms can overwhelm treatment plants, cause sewage overflows, and push runoff into supplies.
06How South Coffeyville compares
Scores for nearby Oklahoma cities on one line, with the average marked.
dashed line = Oklahoma average (45/100)
South Coffeyville scores 86/100 — above the Oklahoma average of 45/100. It outscores 10 of 10 nearby cities. Full Oklahoma rankings →
38.6 / 100DTulsa, OK
48.5 / 100FBroken Arrow, OK
43.9 / 100FNorman, OK
38.4 / 100FLawton, OK
44.4 / 100FEdmond, OK
34.9 / 100
Compare all cities in the county — grades, violations, and contaminant data side by side.→
07What to do at home
Steps matched to what testing actually found in South Coffeyville's water — not generic advice.
A basic carbon filter still helps
South Coffeyville's water meets federal standards, but a simple carbon filter improves taste and adds a margin of safety against short-term issues.
Compare tested filters →Read your utility's annual report
Every utility must publish a yearly Consumer Confidence Report with its own testing results. It pairs well with the independent data on this page.
How to read a CCR →Watch for South Coffeyville alerts
We refresh EPA data monthly and surface new violations, advisories, and boil-water notices for your county on this page.
All water alerts →Frequently asked questions
Is South Coffeyville, OK tap water safe to drink?
South Coffeyville's water quality earned a grade of A- (86/100). The water generally meets EPA standards and is considered safe for consumption. The city ranks #40 out of 357 cities tested in Oklahoma.
What contaminants are in South Coffeyville's water?
Lead was measured at 2.7 ppb (90th percentile). 18 violations are on record.
How is South Coffeyville's water quality grade calculated?
The grade is based on four factors: violation history (40%), lead and copper levels (25%), PFAS contamination (25%), and regulatory compliance (10%). The score is also adjusted based on how complete the available data is. See our methodology page for full details.
Do I need a water filter in South Coffeyville?
Based on current data, basic filtration should suffice for additional peace of mind.
Where does South Coffeyville's water come from?
South Coffeyville's water is sourced from Purchased surface water. The city has 1 water system serving approximately 790 residents.
What health violations has South Coffeyville's water system had?
South Coffeyville has 3 health-based violations on record. The most recent violation was recorded in November 2025. Health-based violations mean the water exceeded EPA maximum contaminant levels (MCLs) for a regulated substance. 2 violations remain unresolved.
How does South Coffeyville's water compare to other cities?
South Coffeyville ranks #40 out of 357 cities in Oklahoma (better than 89% of state cities) and #4972 out of 15382 cities nationally (68th percentile). The grade of A- reflects the combined assessment of violation history, lead and copper levels, PFAS contamination, and regulatory compliance.
Does South Coffeyville's small water system affect quality?
South Coffeyville's system serves approximately 790 residents. Small community water systems (under 3,300 people) may have fewer financial resources for infrastructure upgrades and advanced treatment technologies. However, they are held to the same EPA drinking water standards as larger systems. This system has 18 violations on record.